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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Carter Ellis
Carter Ellis
1,323 Points

Having trouble with groups.py, anyone know what to do from here?

I think I might be forgetting something in the if statement, but I'm not sure

groups.py 
musical_groups = [
    ["Ad Rock", "MCA", "Mike D."],
    ["John Lennon", "Paul McCartney", "Ringo Starr", "George Harrison"],
    ["Salt", "Peppa", "Spinderella"],
    ["Rivers Cuomo", "Patrick Wilson", "Brian Bell", "Scott Shriner"],
    ["Chuck D.", "Flavor Flav", "Professor Griff", "Khari Winn", "DJ Lord"],
    ["Axl Rose", "Slash", "Duff McKagan", "Steven Adler"],
    ["Run", "DMC", "Jam Master Jay"],
]

group_number = 1
if len(musical_groups) = (3)
    for groups in musical_groups:
        print("Group: #{}".format(group_number), ", ".join(groups))
        group_number += 1
nakalkucing
nakalkucing
12,964 Points
nakalkucing
nakalkucing
12,964 Points

Hi Carter Ellis! Have you looked at the Preview Pane? The first problem it indicates is that you have invalid syntax here on line 12:

if len(musical_groups) = (3)
                       ^

Hint: you're attempting to assign len(musical_groups) to (3) right now. Which is impossible.

Let me know if you need more help. :)

Carter Ellis
Carter Ellis
1,323 Points

Thanks nakalkucing! I got it!

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

You're pretty close, all the parts are there, you just need a little re-arranging and some syntax fixups:

  • try doing the length test inside the loop (after the "for" line)
  • also test the individual loop item (groups) instead of the entire list (musical_groups)
  • the comparison operator for equality is "==" (a single "=" is for assignment)
  • an "if" statement should have a colon at the end of the line

Give it another shot with that in mind, and write again if you still have trouble.